Art of briquetting



septH 4, 192s. 1,683,094

' P. C, MULLIGAN ART OF 'BRIQUETTING Filed Oct. 4, 1926 2 Sheets-Sheet l 8 fbg cocu/la VnPoe 01.174,57

O V EN I gwuento Paul C. Mulligan Sept. 4, 192s. 1,683,094

' P. C. MULLIGAN ART OI" BRIQUETTENG Fld Oct. 4, 1926- 2 Sheets-Sheet 2 Nouns ses 2 Winde Ou TLA' r O VEN Fail? C. Mulligan No: In' grd) Patented Sept. 4, 1928.

UNiTED STATES :PAUL C. MULLIGAN, OF SEATTLE, WASHINGTON, ASSIGNOR TO LUTHER J'. HULL,

l 1,683,094 PATENT oF-FICE;

ISAAC M. FOSTER, .A N'D HIMSELF.

Anm or BRTQUETTING.

Application led October 4, 1926. Serial No. 139,381.

My invention relates to the art of briquettiiig, and especially to a briquetting process, or a process of preparing materials for briquetting, in which ordinary molasses is used alone as a binder. Where such molasses has been used heretofore, it has been considered necessary to use high temperatures to drive off the water which is contained in the molasses to enable the briquette to haiden, or to employ a lengthy and time-consuming process at lower temperature, or to employ acids or other materials with the molasses binder.

Inasmucli as high temperatures are inj urious to the base materials, especially when lignite or bituminous coal-is employed, and as it is desirable to speed up the process as much as possible and to ell'ect economy of heat, it is a primary object of the present invention to provide a process for the preparation of materials for briquetting whereby molasses may be used as a binder, in which only low teinperatures are employed, at which temperatures the volatiles will not be driven from coal, if such is used as the base material, and yet a process in which the heat required is conserved and the time for completion of the process is reduced to a minimum.

It is also my object to provide a process which is adaptable to the employment of wood charcoal, or a mixture of wood charcoal with coal, and employing molasses as a binder, for ordinarily it has been found that molasses can not readily be added to charcoal without causing the mass to ball. Hence, `it is a further object to provide a process as especially adapted to the employment of wood charcoal and molasses as a binder therefor, wherein the molasses may readily be mixed with the charcoal and yet one in which the entire process canbe completed quickly and without waste of heat.

The advantages of the roll type press,such as economy of `operation and first cost, rapidity of manufacture, and simplicity, as compared to a punch type press, are well known, and yet it has been -found difficult to prepare briquetting material comprising or containing charcoal and employing a molasses binder for briquetting in a roll type press. The molasses bound mixture in a roll press will not hold together after pressing, due to the inherent characteristics of molasses, requiring special preparation of the materials for briquetting. It is an object of my invention, therefore, to provide a process whereby the and without the addition of special and ex vpensive modifying agents to affect the molasses.

My invention comprises the novell process and the novel steps therein as will be hereinafter described in this specihcation and more particularly as defined by the claimsy terminating the same. rlhe accompanying drawings illustrate several arrangements of apparatus for carrying out my process. t

Figure l illustrates an arrangement adapted for using charcoal alone as the base material. Figure 2 illustrates the apparatus arranged for employing` coal alone or a mixture of coal and charcoal. v

Referring first to the straight charcoal process, it should be understood that wood charcoal is a substance which is extremely difficult and, to a certain degree, dangerous to handle. lt contains a large, amountof line dust and the particles are extremely friable and hence will ily readily into fine dust. It is therefore difficult to grind properly, and the dust, when presentin a confined space, presents the danger of a dust explosion. lt Vis therefore desirable that it be moistened to permit it to be ground, but inasmuch as it must be heated to complete and harden the briquette, the addition of moisture ordinarily presents the problem of later eliminating this moisture with the consequent consumption of heat. n

I have found that the addition of moisture as is required for safe grinding and handling of the charcoal, may be turned to advantage in another way, in that the molasses, having an affinity for or being perhaps somewhat diluted by the water contained within the mass, will readily penetrate to all parts of the mass without causing it'to ball. t forms practically a. homogeneous free handling mixture in which the molasses is thoroughly incorporated. Thus, by the additionof water to the charcoal, it is prevented from dusting and maybe ground readily, and the molasses can thenbe added in suoli a manner that it most readily penetrates the mass and mixes with and coats all particles thereof. The admixture of molasses can occurv as the water is being driven from the mass by heat. Hence the molasses is in a sense substituted for the water, and the water in the molasses can be eliminated by a continuation of the heating.

After elimination of the Water which is inherent in the molasses, and of the waterwhich hadbeenadded to the charcoal, .it is necessary only to cool the mixture and to pass it through a press when the proper temperature has been reached. This temperature,.when

' v straight charcoal is used as the base, is the `ses ordinary atmospheric temperature, or approximately F. VThe mixture at this temperature is readily pressed andthe briquettes formed thus `in a roll type press Will hold their shape. To` complete them, however, it is necessary that they be baked to carbonize the molasses" but this may readily be'doneV by passing them through a heating zone vor oven, by reason of the fact that all excess Waterjhas been eliminated, which requires heating' but for a short period and at a not excessive temperature to `accomplish carbonization of the binder. l Y

By reference to Figure 1, the entire process as relates to the. employment ofcharcoal, Will beunderstood at av glance. The'charcoal is admittedfrom a hopper 1. When iirst admitted, it Willrusually be dry and varying in sizes from line dust to chips. It is passed through a conveyor and mixer, indicated at 2, and upon its delivery to the conveyor a water spray 3 adds suiiicientmoisture to it i to `keep the dust from flying about.V This mixingis ycontinued long enough to thorough-` `ly incorporate the water With the charcoal.

I have oundthat Water to the extent of eight per cent of the charcoal is sufficient to accomplish my purpose.

When this Water is Vthoroughly incorporated into the mass of charcoal, the mixtureV is passed through a grinder, indicated at 4,.

Where it is reduced to a fine powder. The addition of Water prevents this powder from` iyinfr about in the grinder and the entire mass ma e handled by gravity or by other means an delivered from the grinder 4 to` a` hotV mixer 5. A` gas burner 6, or other means, may befemployedto heat the ground vmass as it passes throughthe--mixer 5. In this mannerthe Water is eliminated to a considerable degree, but not entirely. `Prior to entire elimination of the Water, hot molasses from y a tankv12` is admitted to the mixer 5 and this thirty-five perk cent of molasses by molasses, being hot, 'mixes readily with the `maining Water, which Was added' from rthe A second hotl sprayer 3, `is eliminated, and the moisture,

which comprises approximately twenty per cent ofthe molasses, is Valso largely eliminated, but` the mixture is not heated to `the point Wherethewmolasses will begin to carbonize. y A

Vhen tliewater is substantially eliminated from themix, the mixture is delivered to a cooler `8, 'Waterrfoncooling being admitted at 80 and passing out at 8l from the jacket surrounding the-mixer.

dropped upon a conveyor or belt 10 and are passed through an oven l1. In this voven the briquettes are'bake'd for .a vshoittime at a temperature suiiicientto carbonize and harden the molasses and When removed from the Y The material is. advanced through this mixer until itrreaches ordinary room temperature, such as 60013;' It is-thendelivered to a roll type briquetting' press, indicated by the complemental rolls'flf From these,v the finished' briquettes Vare oven and cooled, they will stand anyordinary handling and shipping and, further, 1villA not` Vbreak up when burnedA or if the'ii're is shaken or otherwise disturbed.' This carbonization, or baking of the briquettes maybe doneV in any known manner, the precise" manner in which itis done forming no part` oflmy invention.

The essential eaturesof the process maybe employed for mixtures of charcoaland coal,` or, indeed, may be employed with rawvcoal alone. Reference to Figure 2 Vwill illustrate an arrangement of apparatus for carrying out the process as appliedto coal ormixtures of coal and charcoal: 1

According to this process the raw Ground coal in any percentage desired is delivered from a hopper V2() `to a hot mixer y2l. A gas j et 6 is employed for heating the mixture, or

Vany other suitable means may be used.;l In

this mixer the coalis 'heated and any excess Water 1s` driven therefrom.` It-1s notheated to a point` to drive 0H the volatiles, however; y YIl() Heatedmolassesfrom a tank 12 isthen added.

This molasses is""best inthe propf'urtion-oif` fifteen to thirtyjper cent ofthe-totalweight ot" the briquette.-`

The mixturerof coal and molasses isl` then passed through a further hot mixer 22 where the Water is largely eliminated :from` the molasses. Atthis point, if charcoal is to be Vmixedwith the coal, the cold ground char'- coal is added asfrom a ho per 23. 4If the coaland molasses are mixe vfirst, itis very difficult to mix the charcoal `into this mixture with molassesl binder.` The percentage of molasses and charcoal maybe widely varied and will ordinarily `V availability of these two materials. f

y determined l. by the HND Uponthe addition ofthe `charcoal the mix- Y tureis passed into 4mixer "24wherein the mixing 1s continued Whilethe mass is cool-'f ing. VWater pipes, 25 and 26, are provided as illustrating ameans for coolingthe mix- ISO ture. lhile the cooling is in progress and when the mass has reached a tacky consistency, it is passed into a press, comprising the complemental rolls 9, and is then delivered to a belt conveyor 10, by means of which it is passed through an oven 11, Where the molasses is carbonized, as in the straight charcoal process.

lt will be observed that the mixture must be heated before addition of the molasses. Hence the addition of water to retain the clnircoal in condition for handling requires but little additional heat te eliminate it and the molasses could not be added unless the water were present in the straight charcoal process. hereafter it becomes necessary to eliminate the water inherent in the molasses and the water previously added comprises but small percentage of the water which is ultimately eliminated. Y l

ily eliminating a large portion of the water during the next heating of the mixture, the final baking requires but a short time and but low temperatures. rlhe temperatures are generally sustained, except the mixture must he cooled, to permit it to be pressed properly. it no time, however, do these temperatures rise to a point, nor are they sustained long enough, to drive off any considerable percentage of volatiles from the mass. rflius, there is preserved in the loriqueste the eenibustible volatiles such as are inherent in lignite and bituminous coals.

lfilhat l claim my invention is:

l. rllhe process of briquetting fuel by the use of a molasses binder which consists in heating the basefuel material, adding thereto and mixing therewith the molasses, continuing heating of the mixture to drive off the water contained in the molasses, but maintaining the temperatures throughout below that required to drive off the volatiles, cooling the mixture to a briquetting consistency,

pressing` the mixture, and finally baking the briquettes to carbonize the binder.

2. The process of preparing fuel for briquetting, with the use of a molasses binder, which consists in heating the fuel materials to a point less than sufficient to drive off all volatiles therefrom, adding thereto and mixing therewith the molasses, heating the mixture to drive ofi' the water from the molasses, and` finally cooling the mixture to a briquetting temperature.

3. The process ef preparing volatile-bearing fuel materials for briquetting which consists in heating the fuel material to al point less than sufficient to drive off the volatiles, adding het liquid molasses thereto and mixing the same therewith, further heating the mixture te expel moisture from the fuel and from the molasses, adding finely divided carbenaceeus material to and incorporating it. into the mixture, and finally reducing the temperature of the mass to one suitable for pressing.

4:. The process of briquetting volatile-bearing fuel materials which consists in heating the fuel material to a point less than sufficient to drive H the vola-tiles, adding het liquid molasses thereto and mixing the same therewith, further heating the mixture to expel moisture from the fuel and from the molasses, adding finely divided carbonaceous niateial to and incorporating it into the mixture, and finally reducing the temperature of the mass until the mass reaches a tacky consistency, pressing the individual briquettes, and heating them to carbonize the molasses.

Signed at Seattle, Washington, this th day of September, 1926.

PAUL e. MULLieAN. 

